AWS Certified Solutions Architect – Professional — Question 675
A company is building an image service on the web that will allow users to upload and search random photos. At peak usage, up to 10,000 users worldwide will upload their images. The service will then overlay text on the uploaded images, which will then be published on the company website.
Which design should a solutions architect implement?
Answer options
- A. Store the uploaded images in Amazon Elastic File System (Amazon EFS). Send application log information about each image to Amazon CloudWatch Logs. Create a fleet of Amazon EC2 instances that use CloudWatch Logs to determine which images need to be processed. Place processed images in another directory in Amazon EFS Enable Amazon CloudFront and configure the origin to be the one of the EC2 instances in the fleet.
- B. Store the uploaded images in an Amazon S3 bucket and configure an S3 bucket event notification to send a message to Amazon Simple Notification Service (Amazon SNS). Create a fleet of Amazon EC2 instances behind an Application Load Balancer (ALB) to pull messages from Amazon SNS to process the images and place them in Amazon Elastic File System (Amazon EFS). Use Amazon CloudWatch metrics for the SNS message volume to scale out EC2 instances. Enable Amazon CloudFront and configure the origin to be the ALB in front of the EC2 instances.
- C. Store the uploaded images in an Amazon S3 bucket and configure an S3 bucket event notification to send a message to the Amazon Simple Queue Service (Amazon SQS) queue. Create a fleet of Amazon EC2 instances to pull messages from the SQS queue to process the images and place them in another S3 bucket Use Amazon CloudWatch metrics for queue depth to scale out EC2 instances. Enable Amazon CloudFront and configure the origin to be the S3 bucket that contains the processed images.
- D. Store the uploaded images on a shared Amazon Elastic Block Store (Amazon EBS) volume mounted to a fleet of Amazon EC2 Spot instances. Create an Amazon DynamoDB table that contains information about each uploaded image and whether it has been processed. Use an Amazon EventBridge (Amazon CloudWatch Events) rule to scale out EC2 instances. Enable Amazon CloudFront and configure the origin to reference an Elastic Load Balancer in front of the fleet of EC2 instances.
Correct answer: C
Explanation
Using Amazon S3 for storage combined with Amazon SQS for decoupling is the most scalable, durable, and cost-effective approach for asynchronous image processing. SQS queue depth is the industry-standard metric for scaling an EC2 processing fleet dynamically based on backlog size. Storing the final images in S3 and serving them directly via Amazon CloudFront ensures high-performance, low-latency delivery to users globally, whereas using EFS or EBS is less cost-effective and unnecessarily complex for this workflow.